1. Field of the Invention
The present invention relates to a method for joining members at ordinary temperature for joining a first member and a second member to one another at ordinary temperature.
2. Description of the Related Art
In general, those widely adopted for joining a metal member to another metal member or for joining a metal member to a ceramic member include, for example, the brazing method based on the use of a brazing material, the diffusion brazing method, the friction welding method, and a variety of the welding methods such as the MIG welding and the spot welding.
When such members are joined to one another by means of the brazing method, a brazing material is arranged between the members to be joined. Local heating is effected, for example, by using a burner to heat the brazing material to a temperature not less than its melting point. Thus, the members are joined to one another. However, the brazing method involves the problem that mutual diffusion of components scarcely occurs between the members, and the joining strength is low.
In the case of the diffusion brazing method, the members, which are used as base materials for joining, are heated to a high temperature. Therefore, mutual diffusion of components occurs between the members, and it is possible to obtain a joining strength which is higher than that obtained by the brazing method. However, the diffusion brazing method involves the problem that deformation occurs in addition to annealing and thermal distortion. Further, in the case of the various types of welding methods, the joining strength per unit area is increased, because the metal to be joined is melted. However, the welding methods involve the problem that the deformation of the joined portion is increased.
As described above, in the case of the respective joining methods described above, it is known that the distortion hysteresis remains at ordinary temperature, and the thermal distortion appears, because the metal or the ceramic to be joined is exposed to a high temperature. Further, for example, the distortion is also caused by partial application of heat, and the fatigue characteristic is affected thereby. Thus, various troubles arise due to the application of heat.
In order to avoid the occurrence of thermal distortion, the friction welding method is adopted, as a joining method for performing joining at ordinary temperature or in the vicinity thereof. In the case of the friction welding method, atoms of both members to be joined make direct diffusion, in which it is possible to obtain an extremely high strength, and it is possible to effectively reduce the occurrence of distortion.
However, in the case of the friction welding method described above, a lot of burrs are formed at the joined portion between the members. Therefore, it is necessary to remove the burrs in the next step. For this reason, the following problem is pointed out. That is, special equipment is required to remove the burrs, and the size of joinable member is restricted.